Solenoid-operated valve

ABSTRACT

A solenoid-operated valve having a valve stem sealed by a flexible metallic bellows, the stem having a shoulder and the bellows having a stem flange with a cylindrical collar fitting closely on the stem and sealed against and circumferentially fused or welded to the stem of the shoulder. The stem flange has concentric undulations outwardly of the collar to impart flexibility thereto. The bellows also has a base flange with concentric undulations and a cylindrical offset between the outer undulation and a flat marginal flange. This flange is clamped against an abutment formed in the valve body, and an O-ring is disposed in a recess in the valve body and is compressed between said flange and the cylindrical offset. The bellows further comprises a number of intermediate convolutions, each consisting of a pair of annular diaphragms having their inner and outer marginal peripheries fused or welded together, and also provided with undulations to impart flexibility. The valve stem carries a partially spherical head at its lower end, which engages a sharpedged seat in the valve body. The valve body may include more than one valve, with the valve stems thereof independently operated by different solenoids.

United States Patent 1 Boggs [451 Sept. 4, 1973 1 SOLENOID-OPERATEDVALVE [75] Inventor: Weldon C. Boggs, Tampa, Fla.

[73] Assignee: Food Research & Equipment Company, Tampa, Fla.

[22] Filed: Sept. 23, 1970 [21] Appl. No.: 74,648

[52] U.S. CI. 251/335 [51] Int. Cl. Fl6k 41/04 [58] Field of Search251/335 B, 141, 214; 137/608 [56] References Cited UNITED STATES PATENTS1,478,815 12/1923 Blauvelt 251/335 B 2,888,037 5/1959 Jones et a1.251/335 B 3,423,064 l/l969 Harland et a1. 251/214 X 3,567,176 3/1971Johnson 251/214 X 2,114,139 4/1938 Crosthwait, Jr. et a1 251/335 B3,253,611 5/1966 Cummins 251/337 X 3,399,697 9/1968 Schwartz... 137/608X 1,548,122 8/1925 Dunham.... 251/335 B 3,366,288 l/1968 Goldschein251/141 X 2,693,822 11/1954 Gerow et a1 251/335 B 1,527,154 2/1925Mallory et al.... 251/335 B 1,727,281 9/1929 Fulton 251/335 B 2,642,8906/1953 Skewis 251/335 B 2,880,620 4/1959 Bredtschneider 251/335 BPrimary Examiner-Samuel Scott AttorneyBacon & Thomas [5 7] ABSTRACT Asolenoid-operated valve having a valve stem sealed by a flexiblemetallic bellows, the stem having a shoulder and the bellows having astem flange with a cylindrical collar fitting closely on the stem andsealed against and circumferentially fused or welded to the stem of theshoulder. The stem flange has concentric undulations outwardly of thecollar to impart flexibility thereto. The bellows also has a base flangewith concentric undulations and a cylindrical offset between the outerundulation and a flat marginal flange. This flange is clamped against anabutment formed in the valve body, and an O-ring is disposed in a recessin the valve body and is compressed between said flange and thecylindrical offset. The bellows further comprises a number ofintermediate convolutions, each consisting of a pair of annulardiaphragms having their inner and outer marginal peripheries fused orwelded together, and also provided with undulations to impartflexibility. The valve stem carries a partially spherical head at itslower end, which engages a sharp-edged seat in the valve body. The valvebody may include more than one valve, with the valve stems thereofindependently operated by different solenoids.

10 Claims, 6 Drawing Figures SOLENOID-OPERATED VALVE FIELD OF THEINVENTION valve having a novel stem, long-lived bellows, and bodyconstruction designed to provide trouble-free operation and to preventleakage along the stem.

DESCRIPTION OF THE PRIOR ART Solenoid-operated valves including a stemsealed by a bellows have been known heretofore, but one of theobjections to prior valves of this type is that they do not provide along-lasting seal for the valve stem and soon leak. Another objection isthat the bellows usually comprises thin, metal diaphragm sections thatbecome fatigued and crack after a period of use, resulting in leakageand rendering the valve useless. The foregoing objections have beenovercome by the present invention, wherein the lower end of the bellowshas a stem flange that is permanently sealed with the valve stem and theupper end of the bellows has a base flange that is sealed with the valvebody by an O-ring maintained under compression. Fatigue and cracking ofthe metal diaphragm sections is avoided by providing concentricundulations therein, which greatly increase their flexibility andconsequently their resistance to fatigue. A test conducted with a valveand bellows designed in accordance with the principles of the presentinvention has withstood well over one-half million contracting andexpanding actions without failure.

SUMMARY OF THE INVENTION The present invention relates to a multiplesolenoidoperated valve comprising a single body and a pair of valvesindividually operated by a solenoid connected with the valve stem ofeach of the valves. The valve body has a single inlet port and twooutlet ports, flow through the outlet ports being controlled by theseparately operable valves. The valve body also includes cavitiesaligned with the outlets to receive a subassembly of a valve stem andbellows, each of which subassemblies is maintained in place in the valvebody by a removable retainer. Each reatiner contains a TEF- LON bushingfor the valve stem. Each retainer also has a threaded extension forsecuring it to a mounting plate. Each valve stem extends beyond thethreaded extension when the valve is fully closed and is connected by alink with a solenoid. The lower end of the valve stem carries apartially spherical'head that engages with a sharp-edged valve seatassociated with each outlet port of the valve. However, the valve headand valve seat are not novel per se and form no part of the presentinvention, since generally similar structures are shown in French Pat.No. 494,261 and US. Pat. Nos. 2,073,112, 2,360,945 and 2,859,765. I

The present valve is especially well adapted for use in a deep fat fryerof the type including a system through which hot cooking oil is cycled,and which cooking oil may contain entrained soft solids, such as batterand food particles. Hence, the valve includes a sharp seat and apartially spherical valve head having line contact for cutting throughsoft solids and thus-assuring tight closing of the valve. In thisconnection, the bellows is heat-treated to impart spring-like tensionthereto, for maintaining the valve head engaged with its seat when thesolenoid controlling the valve is deenergized.

Accordingly, the principal object of the invention is to provide asolenoid-operated valve having an improved leak-proof, valve stem andbellows construction. I

Another object is to provide a solenoid-operated valve, wherein thebellows has a longer useful life than bellows of similar type valvesheretofore available.

Another object is to provide a solenoid-operated valve including abellows that can be satisfactorily used to handle liquids at hightemperatures and maintain a permanent seal with a valve stem, andwherein the valve stem is so mounted that it will not stick in its guidemeans.

Still another object is to provide a bellows that is resilient andinherently provides a force tending to urge the valve stem connectedthereto toward closed position, so that the valve will remain positivelyclosed until the solenoid connected with the valve stem for operatng thevalve is energized.

Still another object is to provide a valve stem and bellows subassemblythat can be readily mounted in and removed from a valve body.

Other objects and advantages of the invention will become apparent fromthe following descriptions taken in conjunction with the accompanyingdrawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view througha solenoidoperatedvalve having two valve stems with bellows sealsconstructed in accordance with the principles of.

the present invention;

FIG. 2 is a plan view of the valve as viewed on the line 2-2 of FIG. 1;

FIG. 3 is an enlarged fragmentary sectional view through the valveillustrating the details of the manner in which the lowermost section,orstem flange, of the bellows is secured to the stem, and the manner inwhich the uppermost section of the bellows, or base flange, is

DESCRIPTION OF THE PREFERRED EMBODIMENT- Referring to FIG. 1, the valvebody is generally identified by the numeral 2 and may be made from ablock of aluminum, or cast from aluminum, stainless steel, or any othersuitable metal. The bocks 2 has a blind longitudinal inlet passageway orport 4 provided with threads 6 at its outer end to receive a pipe 8,which may serve as a supply pipe. The valve body 2 has ports 10 and 12,which intersect the passageway 4, and serve as outlet ports. The port 10has threads 14 atits outer end in which a pipe 16 is mounted, and theport 12 has threads 18 in which a pipe 20 is mounted. The ports 10 and12 are counterbored at their upper end to provide seats 22 and 24,respectivelyfThe side wall of the ports l0 and 12 is vertical, while thebottom of the counterbores 22 and 24 is horizontal, so that the seats 22and 24 have a sharp right angle corner or cutting edge.

The valve body 2 contains vertical chambers 26 and 28, which alsointersect with the passageway 4 and are axially aligned with the portsand 12, respectively. The chamber 26 is enlarged at its upper end andhas threads 30 into which a retainer plug 32 is threaded. The plug 32has a passage 34 that is enlarged at its lower end to form a recess 36in which a cylindrical TEFLON bushing 38 is mounted.

The bushing 38 is held in place by peening the lower end of the retainer32 adjacent the recess 36, as indicated at 40. The plug 32 has athreaded axial extension 42 that extends through an opening 44 in aplate 46. A nut 48 is mounted on the extension 42 and secures the plate46 to the plug 32. A stainless steel valve stem 50 is slidably mountedin the bushing 38 and has a partially spherical valve head 52 at itslower end for engaging the seat 22 with line contact. The stem 50 is ofsuch length that its upper end extends beyond the extension 42 when thevalve head 52 is engaged with the seat 22.

An opening 54 is formed in the upper end of the stem 50 to receive a pin56, which pivotally connects the stem to a link 58. The upper end of thelink 58 is pivotally connected by a pin 60 to an armature 62 of aconventional electromagnet or solenoid 64. Spacers 66 have threadedopenings 68 at their lower end to receive screws 70, which securd thespacers to the plate 46. A second plate 72 is similarly secured to theupper end of the spacers 66 by screws 74. The solenoid 64 carriesbrackets 76 that are secured to the plate 72 by bolts 78, as shown.Electrical leads 8] and 83 are connected to a coil 85 of the solenoidfor supplying current to energize the same and open the valve 52.

The plates 46 and 72 and the spacers 66 provide a frame for supportingthe solenoid 64 that operates the valve 52. The valve head 52 isengagable with the sharp edge of the seat 22 so as to close withsubstantially line contact. This construction enables the valve head 52to cut through any soft solids that may be entrained in the liquidflowing through the valve at the time the solenoid 64 is de-energized tolet the valve close.

A fluid-tight seal for the stem 50 is provided by a resilient metallicbellows generally identified by the numeral 80. Referring to FIG. 3, thestem 50 has an upper portion 82 of smaller diameter than the portionthereof adjacent the valve head 50, whereby the juncture of the twocylindrical portions provides a horizontal shoulder 84. A groove 86semicircular in radial cross section is cut into the stem 50 adjacentthe shoulder 84 to provide a flange 88 having a narrow marginal edge.

The bellows 80 consists of a series of annular diaphragm sectionsconnected together in a manner which will be described more fullyhereinafter. The lowermost section, or stem flange of the bellows, isidentified by the numeral 92, FIG. 4, and includes a dependingcylindrical collar 94 closely fitting the stem portion 82 and having itsend abutting the shoulder 84, and being fused or welded theretothroughout its circumference to provide a tight seal between the two.The narrow marginal edge of the flange 88 facilitates such operation.The section 92 has a flat central area 96 immediately adjacent thecollar 94, and also has a flat marginal edge 98. The flat central area96 extends outwardly for a distance of about one-third of the radiallength between the collar 94 and the outer periphery of the marginalportion 96, the intermediate area having concentric undulations 100. Thepurpose of the undulations 100 is to render the stem flange section 92flexible so that it will function satisfactorily indefinitely withoutcracking or fracturing from fatigue.

The uppermost section, or base flange, of the bellows 80 is identifiedby the numeral 102 (FIG. 5) and comprises a flat marginal inner portin104 adjacent to which is a flat annular portion 108 surrounded byundulations 106, which blend into a vertically offset cylindricalportion 110, having substantially the same outside diameter as the outerdiameter of the stem flange section 92. A horizontal flange 112 extendsoutwardly from the upper edge of the offset 110. The section 102 has acentral opening 114 to receive the valve stem 50. A shallow depressionsurrounds the opening and is defined in part by the flat inner marginalportion 104.

The remainer of the bellows 80 consists of convolutions each includingan upper diaphragm 116 and a lower diaphragm 118. Each of the diaphragms116, l 18 has flat inner and outer marginal portions 120 and 122respectively with concentric undulations therebetween arranged so thatthe diaphragms can nest relative to each other. The inner marginalportions 120 surround an openig through which the valve stem extends.The inner and outer marginal portions 120 and 122 of adjacent sectionsare fused or welded together throughout their periphery as indicated at121 and 123, so that the bellows is leakproof.

As is best shown in FIG. 3, the valve body 2 has a shallow annulardepression 124 to receive the flange or rim 112 of the base flange 102.This rim is clamped in place by the lower face of the retainer plug 32.The valve body 2 is counterbored at 126 to provide a shoulder forming arecess 128 to receive an O-ring 130 that forms a seal between the valvebody, the rim 1 12 of the base flange 102 and the cylindrical offset110.

The plug 32, FIG. 2, has a vent passage 132 that establishescommunication between the interior of the bellows and the outsideatmosphere. This eliminates the possibility of any air pressuredeveloping within the bellows 80, and also serves as a means fordetecting leakage past the valve stem 50 should any occur.

FIG. 6 illustrates the general method of assembly of the intermediatesections of the bellows, that is, the convolutions lying between thestem flange 92 and the base flange 102. Thus, each convolution of thebellows comprises the upper and lower diaphragms 116 and 118. Infabricating the same, the inner margins of an upper and lower diaphragmare welded or fused together at their inner periphery as indicated at121, and then sections consisting of the two diaphragams are placed incontact and welded or fused together at their outer margin 122, asindicated at 123. At such time, the stem flange 92 and the base flange102 are fused or welded in place. The assembled bellows 80 can thus bewelded to the stem 50 at the collar 94 and flange 88.

A device embodying the principles of the present invention may includeany desired number of valves, but

' for illustrative purposes two valve and two solenoids have been shown.These are identical and in the interest of brevity, the stem of thesecond valve has been identified by the numeral 50A, and the valve headby the numeral 52A. The remaining corresponding parts have been giventhe same number as used in the foregoing description. The valves 52 and52A have a stroke of about l/2 inch, but the length of the stroke may bevaried as desired. In any event, it is preferable to design the valvebody so that the bellows 80 is out of the path of flow of the liquidwhen either of the valves 52 or 52A is closed. This condition can bereadily visualized by observing the position of the bellows 80 inconnection with the closed valve 52 in FIG. 1.

The present valve is especially designed to handle hot liquid, forexample, cooking oil at temperatures which I may range up to 400 F andhigher. Smooth and free operation of the valve stems 50 and 50A isassured by having the stems slide in the TEFLON bushings 38. Thesebushings not only resist high heat, but require no special lubricant toeliminate sticking of the valve stems.

In the operation of the valve, it will be understood that the valves 52and 52A can be independently opened, or if desired, both valves can besimultaneously held openby energizing the solenoids 64. Flow through thevalve body 2 may be in any direction desired, so long as at least one ofthe valves 52 or 52A is open. The spring tension built into the bellows80 will maintain the associated valves in closed position when thesolenoids 64 are de-energized. It will be understood that the weight ofthe solenoid armature 62, link 58 and the weight of the valve stems 50and 50A themselves will aid in maintaining the valves closed when theelectromagnetic coils 84 are de-energized. The bellows 80 may have anynumber of convolutions depending upon the enrironment in which it is tobe used.

It will be understood that various changes may be made in the details ofthe design and construction of the present valve without departing fromthe principles of the invention or the scope of the annexed claim.

I claim:

1. A valve construction, comprising: a body having a passageway and atleast one port communicating with said passageway and having a valveseat surrounding said port; a valve including a stem axially alignedwith said seat, said stem having a narrow radial shoulder formedthereon; a bellows mounted upon said stem having an annular stem flangeat one end thereof provided with an axially extending collar at itsinner margin closely fitting said stem with the collar abutting saidshoulder, said collar being circumferentially welded or fused to saidshoulder, said body having a cavity in which the bellows is received anda shallow recess surrounding the upper end of said cavity, said recesshaving a bottom, said bellows including a base flange having a rimreceived in said recess; and a retainer plug threaded into said cavityand engaging said rim to clamp the same against the bottom of saidrecess, said retainer plug having a bore containing a TEFLON bushingreceiving the valve stem therein and serving as a guide for said valvestem.

2. In a valve, the sub-combination comprising: a cylindrical valve stemhaving a narrow radial shoulder; and a bellows including an annular stemflange at one end thereof having an axially extending collar at itsinner margin closely fitting said stem with the edge of the collarabutting said shoulder, said collar being circumferentially welded orfused to said shoulder, said bellows including a base flange at itsother end, said base flange having a central opening defining an innermargin surrounding the valve stem, said base flange having undulationsoutwardly of saidv inner marginal edge, and having a cylindrical offsetportion adjacent the outermost undulation and an outwardly extending rimprojecting from the upper edge of said cylindrical offset portion.

3. A valve construction, comprising: a body having a passageway and atleast one port communicating with said passageway and having a valveseat surrounding said port; a valve including a stem axially alignedwith said seat, said stem having a narrow radial shoulder formedthereon; a bellows mounted upon said stem having an annular stem flangeat one end thereof provided with an axially extending collar at itsinner margin closely fitting said stem with the collar abutting saidshoulder, said collar being circumferentially welded or fused to saidshoulder, said body having a cavity in which the bellows is received anda shallow recess surrounding the upper end of said cavity, said recesshaving a bottom, said bellows including a base flange having a rimreceived in said recess; a retainer plug threaded into said cavity andengaging said rim to clamp the same against the bottom of said recess,said base flange including a cylindrical offset at the inner margin ofthe rim, said valve body also having a counterbore disposed radiallyinwardly of the shallow recess and confronting said offset cylindricalportion; and an O-ring disposed in said counterbore and being engaged bysaid cylindrical offset portion and by said rim and compressed to form aseal between the valve body and the base flange of the bellows.

4. A valve construction as defined in claim 3, wherein a solenoid isconnected with the valve stem; and wherein the bellows has springtension built into it to maintain the valve closed when the solenoid isdeenergized.

5. A valve construction, comprising: a body having a passagewayextending lengthwise thereof and serving as an inlet, and having a pairof outlet ports intersecting said passageway and having a valve seatsurrounding each of said outlet ports, said body also having a chamberaligned with each of said outlet ports; a valve including a valve stemaxially aligned with each of said outlet ports, each of said valve stemshaving a narrow radial shoulder formed thereon; a bellows mounted uponeach of said valve stems and having an annular stem flange at one endthereof provided with an axially extending collar at its inner marginclosely fitting said valve stem with the collar abutting said shoulder,said collar being circumferentially welded or fused to said shoulder;and a solenoid connected with each valve stem. I

6. A valve construction as defined in claim 5, wherein each solenoidincludes an armature, and a link is disposed between each armature andvalve stem and is pivotally connected to both.

7. A valve construction, comprising: a body having a passageway and atleast one port communicating with said passageway and having a valveseat surrounding said port; a valve including a stem axially alignedwith said seat, said stem having a narrow radial shoulder formedthereon; a bellows mounted upon said stem having an annular stem flangeat one end thereof provided with an axially extending collar at itsinner margin closely fitting said stem with the collar abutting saidshoulder, said collar being circumferentially welded or fused tosaid'shoulder, said body having a cavity in which the bellows isreceived and a shallow recess surrounding the upper end of said cavity,said recess having a bottom, said bellows including a base flange havinga' rim received in said recess; a retainer plug threaded into saidcavity and engaging said rim to clamp the same against the bottom ofsaid recess, said retainer plug having a threaded axial extension; aframe having a member provided with an opening, said extensionprojecting through the opening in the frame memher and being secured tosaid frame member; and a solcnoid mounted upon the frame and connectedwith the valve stem.

8. A valve construction as defined in claim 7, wherein the frame memberis a plate, and wherein the frame further comprises a second plate, anda plurality of spacers mounted between said plate and wherein thesolenoid is mounted on said second plate and is disposed between saidspacers.

9. In a valve, the sub-combination comprising: a cylindrical valve stemhaving a narrow radial shoulder;

1. A valve construction, comprising: a body having a passageway and atleast one port communicating with said passageway and having a valveseat surrounding said port; a valve including a stem axially alignedwith said seat, said stem having a narrow radial shoulder formedthereon; a bellows mounted upon said stem having an annular stem flangeat one end thereof provided with an axially extending collar at itsinner margin closely fitting said stem with the collar abutting saidshoulder, said collar being circumferentially welded or fused to saidshoulder, said body having a cavity in which the bellows is received anda shallow recess surrounding the upper end of said cavity, said recesshaving a bottom, said bellows including a base flange having a rimreceived in said recess; and a retainer plug threaded into said cavityand engaging said rim to clamp the same against the bottom of saidrecess, said retainer plug having a bore containing a TEFLON bushingreceiving the valve stem therein and serving as a guide for said valvestem.
 2. In a valve, the sub-combination comprising: a cylindrical valvestem having a narrow radial shoulder; and a bellows including an annularstem flange at one end thereof having an axially extending collar at itsinner margin closely fitting said stem with the edge of the collarabutting said shoulder, said collar being circumferentially welded orfused to said shoulder, said bellows including a base flange at itsother end, said base flange having a central opening defining an innermargin surrounding the valve stem, said base flange having undulationsoutwardly of said inner marginal edge, and having a cylindrical offsetportion adjacent the outermost undulation and an outwardly extending rimprojecting from the upper edge of said cylindrical offset portion.
 3. Avalve construction, comprising: a body having a passageway and at leastone port communicating with said passageway and having a valve seatsurrounding said port; a valve including a stem axially aligned withsaid seat, said stem having a narrow radial shoulder formed thereon; abellows mounted upon said stem having an annular stem flange at one endthereof provided with an axially extending collar at its inner marginclosely fitting said stem with the collar abutting said shoulder, saidcollar being circumferentially welded or fused to said shoulder, saidbody having a cavity in which the bellows is received and a shallowrecess surrounding the upper end of said cavity, said recess having abottom, said bellows including a base flange having a rim received insaid recess; a retainer plug threaded into said cavity and engaging saidrim to clamp the same against the botTom of said recess, said baseflange including a cylindrical offset at the inner margin of the rim,said valve body also having a counterbore disposed radially inwardly ofthe shallow recess and confronting said offset cylindrical portion; andan O-ring disposed in said counterbore and being engaged by saidcylindrical offset portion and by said rim and compressed to form a sealbetween the valve body and the base flange of the bellows.
 4. A valveconstruction as defined in claim 3, wherein a solenoid is connected withthe valve stem; and wherein the bellows has spring tension built into itto maintain the valve closed when the solenoid is deenergized.
 5. Avalve construction, comprising: a body having a passageway extendinglengthwise thereof and serving as an inlet, and having a pair of outletports intersecting said passageway and having a valve seat surroundingeach of said outlet ports, said body also having a chamber aligned witheach of said outlet ports; a valve including a valve stem axiallyaligned with each of said outlet ports, each of said valve stems havinga narrow radial shoulder formed thereon; a bellows mounted upon each ofsaid valve stems and having an annular stem flange at one end thereofprovided with an axially extending collar at its inner margin closelyfitting said valve stem with the collar abutting said shoulder, saidcollar being circumferentially welded or fused to said shoulder; and asolenoid connected with each valve stem.
 6. A valve construction asdefined in claim 5, wherein each solenoid includes an armature, and alink is disposed between each armature and valve stem and is pivotallyconnected to both.
 7. A valve construction, comprising: a body having apassageway and at least one port communicating with said passageway andhaving a valve seat surrounding said port; a valve including a stemaxially aligned with said seat, said stem having a narrow radialshoulder formed thereon; a bellows mounted upon said stem having anannular stem flange at one end thereof provided with an axiallyextending collar at its inner margin closely fitting said stem with thecollar abutting said shoulder, said collar being circumferentiallywelded or fused to said shoulder, said body having a cavity in which thebellows is received and a shallow recess surrounding the upper end ofsaid cavity, said recess having a bottom, said bellows including a baseflange having a rim received in said recess; a retainer plug threadedinto said cavity and engaging said rim to clamp the same against thebottom of said recess, said retainer plug having a threaded axialextension; a frame having a member provided with an opening, saidextension projecting through the opening in the frame member and beingsecured to said frame member; and a solenoid mounted upon the frame andconnected with the valve stem.
 8. A valve construction as defined inclaim 7, wherein the frame member is a plate, and wherein the framefurther comprises a second plate, and a plurality of spacers mountedbetween said plate and wherein the solenoid is mounted on said secondplate and is disposed between said spacers.
 9. In a valve, thesub-combination comprising: a cylindrical valve stem having a narrowradial shoulder; and a bellows including an annular stem flange at oneend thereof having an axially extending collar at its inner marginclosely fitting said stem with the edge of the collar abutting saidshoulder, said collar being circumferentially welded or fused to saidshoulder, said valve stem having a groove therein adjacent the shoulderto form a narrow flange to facilitate the welding or fusing of saidcollar thereto.
 10. The sub-combination defined in claim 9, wherein thestem flange has concentric undulations formed therein outwardly of thecollar to render the same flexible.